Abstract: Ni3Al has attractive high temperature properties, such as high strength and good
oxidation/corrosion resistance, and is possible to be used for high temperature chemical processing and manufacture. Until now, the catalytic properties of Ni3Al were rarely investigated since the leaching of aluminum from Ni3Al is difficult to obtain a porous Raney-Ni compared to NiAl3 and Ni2Al3. In the present work, the catalytic properties of Ni3Al were examined for hydrogen production reactions from methanol. It was found that alkali-leached Ni3Al showed high activity for methanol decomposition (CH3OH→ 2H2+CO). Furthermore, Ni3Al catalysts suppress the formation of methane, i.e. they show higher selectivity for the methanol decomposition reaction than Ni catalyst. These results indicate a possibility for Ni3Al used as a catalyst for hydrogen production reaction.

Abstract: Bamboo forest was a dominantly ecological and sustainable economic recources. However, bamboo extractives and hemicellulose were nearly complete dissolved out in preparation of the fiber, this would result in more serious water pollution and meanwhile bring a great waste of biological resources. Thereby, In order to obtain the way to lower the negative impact of the extractives and hemicellulose, the Phyllostachys pubescens biomass was treated in alkaline solutions at room temperature and the extractives obtained was analyzed by SIZER basen on the full-factor method. The results were following as: (1) Sort of alkaline and concentration of alkaline had a significant influence on the leaching rate of particles at 0.01 level. And the optimal concentrations of KOH, NaOH, LiOH were 16.0%, 17.5% and 17.5% at 25°С, respectively. (2) Pretreatment, extraction time and sort of alkaline had no influence on the leaching rate of particles. But the benzene/ethanol pretreatment was valuable and necessary. when 16% NaOH and 17.5% KOH were used, the optimal extraction time were all 16h to untested and tested samples.

Abstract: The bioleaching effect of different concentrations of silver ion catalysis on chalcopyrite tailings has been investigated in shaking flasks. In this paper, A.t ferrooxidans were selected for conducting the bioleaching process. Experiments were carried out under the condition of pulp density 150 g/L, inoculation amount 106~7 cells/mL, pH around 2.0, culture temperature 30°C, rotation speed 150 r/min. The silver ion concentrations varied from 0 to 0.05g/L. After a bioleaching time of 24 days, 82% and 55% of copper was dissolved from the ore for the silver ion concentration of 0.01 g/L and 0.001 g/L respectively, compared with only 37% and 13% recovery for the silver ion concentration of 0 and 0.05 g/L. Preliminary tests showed that the silver ion concentration had a markedly catalytic effect on the copper extraction. The experimental results also showed that high silver ion concentration would inhibit the copper extraction. That was because the silver ions at high concentrations are toxic and they can suppress the bacteria growth and oxidation activity.

Abstract: The content of SiO2 was more than 60% in the residue of pyrolusite detached manganese by reduction roasted and acid leached, and it was a better siliceous raw material because of less other impurities. Through leaching silicon process in the residue of pyrolusite with alkali at atmospheric pressure, leaching kinetics of silica in the sodium hydroxide solution was researched. The effects of the leaching temperature and the concentration of sodium hydroxide solution on the leaching behavior of silica from acid-leached pyrolusite slag were examinted. It was found that the extracting rate of silica is significantly influenced by the temperature, and the concentration of NaOH solution. The experimental datas were well interpreted with a shrinking core model under chemical control. On the basis of the Arrhenius expression the apparent activation energy of 77.69 kJ/mol and a reaction order of 0.34 for the extraction of silica was evaluated.

Abstract: The leaching characteristics of chemical components from converter steel slag were studied through circulating leaching experiments. Results show that the most quality of leaching is CaO, SiO2 is the second and Al2O3 is the least. Analyzing the leaching process and experimental results, it can conclude that the leaching kinetics is controlled by intra-paticle diffusion. The leaching process can be described by shrinking unreacted core model.